A top US military commander in Iraq has said he expects more attacks as the US prepares to hand over power to Iraqis.
Sanchez: We haven't found the right haystack yet
"We expect to see an increase in violence as we move toward sovereignty at the end of June," General Ricardo Sanchez told reporters on Sunday.
He added the hunt for Saddam Hussein was continuing, but that it was like looking for a needle in a haystack.
His comments came shortly after a US soldier was killed by a roadside bomb in the northern city of Mosul.
General Sanchez said the US assumed that Saddam Hussein was still in Iraq.
"Clearly we haven't found the right haystack. We're all focused on finding that needle," he said.
But he said he did not expect attacks on coalition troops to end if Saddam Hussein was found.
"The killing or capturing of Saddam Hussein will have an impact on the level of violence, but it will not end it," he said.
General Sanchez said the number of military engagements was down to less than 20 a day, compared to almost 40 a day in early November.
A tribal chief told the French news agency AFP that the ousted leader was directing attacks against the coalition.
"The Iraqi president is commanding the military operations against the American forces," said the loyalist who called himself Abu Mohammad.
He said the former leader was "in good health and living in the west of Iraq," AFP reported.
Rumsfeld has visited Iraq three times since the end of the war
Visiting Iraq a day before General Sanchez's remarks, US Defence Secretary Donald Rumsfeld said the US would put security operations in the hands of local forces next year as planned.
Mr Rumsfeld also urged the Governing Council to resolve outstanding issues over the transfer of sovereignty.
During Mr Rumsfeld's visit, General Sanchez said the latest US offensive targeting insurgents' cells was yielding results.
Mr Rumsfeld said that was a good sign - but it should not be overemphasised.
Mr Rumsfeld met members of the new Iraqi civil defence corps in Baghdad.
He said he was satisfied that they would be capable of looking after the security of the country.
In November, the Americans suffered their worst monthly toll of casualties since major combat was declared over on 1 May, losing 79 soldiers mostly in enemy attacks.